1,3-β-Glucanase from Vigna aconitifolia and its possible use in enzyme bioreactor fabrication

Endo-1,3(4)-β-glucanase (EC 3.2.1.6) from Vigna aconitifolia sprouts was purified to 14.5 fold by gel filtration and ion-exchange chromatography. The enzyme was found to be a glycoprotein, its activity was Ca2+ dependent and specific for β-1,3 linkages in different polysaccharides. The Km value of the enzyme was estimated to be 3.0 mg ml−1 for β-d-glucan as substrate. Circular dichroism studies revealed 8% α-helix, 48% β-pleated and 44% random coil in its secondary structure. Purified β-glucanase was then successfully co-immobilized with glucose oxidase in agarose-chitosan beads, showing better immobilization yield, operational range and stability as compared with the crude β-glucanase beads. The immobilized β-glucanase was successfully used for mini-bioreactor fabrication.